0000000000266488

AUTHOR

J. Casanova

Metal complexes of sulfanilamide derivatives. Spectroscopic characterization of the dichloro disulfathiazole methanol copper(II) complex

The synthesis and spectral characterization of the [Cu(Hstz)2(MeOH)Cl2] complex are described. Both polycrystalline powder EPR and single crystal EPR spectra recorded at room temperature show rhombic distortion with values of g1=2.25, g2=2.09 and g3=2.03 in agreement with a copper polyhedron, intermediate between trigonal bipyramid and square pyramidal.

research product

Metal complexes of the carbonic anhydrase inhibitor methazolamide (Hmacm). Crystal structure of the Zn(macm)2 (NH3)2. Anticonvulsant properties of the Cu(macm)2 (NH3)3(H2O)

Complexes of Co(II), Cu(II), and Zn(II) with deprotonated methazolamide and ammonia are synthesized and characterized. The complex Zn(macm)2(NH3)2 crystallizes in the monoclinic C2/c space group with a = 13.468(1), b = 6.759(1), c = 23.014(2) A, beta = 90.27(1), and Z = 4. The structure was refined to R = 0.049 (Rw = 0.053). The Zn(II) ion is coordinated to two deprotonated sulfonamido nitrogen atoms of the macm- ligand and two nitrogen atoms of the ammonia ligands in a distorted tetrahedron. The Zn(macm)2(NH3)2 complex is shown to be a simple model for the methazolamide inhibition of CA. EHMO calculations applied to fractional coordinates of the Zn(macm)2(NH3)2 complex indicate that the at…

research product

A Co(III) complex of carbonic anhydrase inhibitor methazolamide and the amino-imino ‘aib’ ligand formed by reaction of acetone and ammonia

Abstract Reaction of Co(NO 3 ) 2 ·6H 2 O with methazolamide {[ N -(3-methyl-5-sulfamoyl-1,3,4-thiadiazol-2(3 H )-ylidene)acetamide] (Hmacm)} and ammonia in acetone to produce [Co(methazolamidate)(2-methyl-2-amino-4-iminopentane) 2 (NH 3 )](NO 3 ) 2 ·2H 2 O is described. The ligand 2-methyl-2-amino-4-iminopentane (aib) is the product obtained from the condensation of two ammonia and two acetone molecules. The complex crystallizes in the monoclinic space group P 2 1 / c with a =16.713(5), b =9.180(1), c =20.273(1) A, β=97.44(4)° for Z =4. The R value is 0.081 for 2150 significant reflections. The Co(III) ion exhibits a nearly regular octahedral arrangement with the CoN bond distances in the …

research product

Copper complexes modelling the interaction between benzolamide and Cu-substituted carbonic anhydrase. Crystal structure of Cu(bz)(NH3)4 complex

New copper benzolamide (H 2 bz, 5-phenylsulfonamide-1,3,4-thiadiazole-2-sulfonamide) complexes with ammonia, diethylentriamine (dien) and dipropylentriamine (dipn) have been prepared. The complex [Cu(bz)(NH 3 ) 4 ] crystallises in the monoclinic space group P 2 1 / n with a = 7.621(3), b = 19.91(5), c = 11.291(3) A, β = 93.17(4)° and Z = 4. The Cu(II) is five-coordinated with an almost regular square pyramidal geometry. The dideprotonated sulfonamide behaves as monodentate ligand interacting with the metal ion through the N atom of the unsubstituted sulfonamide group. In the EPR spectrum, exchange coupling between Cu(II) polyhedra of different orientations in the unit cell is observed. The …

research product

Coordination behavior of sulfathiazole. Crystal structure of [Cu (sulfathiazole) (py)3Cl] superoxide dismutase activity

Abstract The preparation, spectroscopic, magnetic properties, and crystal structure of [Cu(stzxpy) 3 Cl] (stz − stands for the deprotonated form of sulfathiazole, 4-amino-N-2-thiazolylbencenosulfonamide) are reported. Crystals are orthorhombic, space group Pbca, with cell constants a = 15.834(2), b = 17.512(4), and c = 18.79(2) A, and Z = 8. The structure was solved and refined to R = 0.041 (R W = 0.040). The structure consists of mononuclear units linked via hydrogen bonds to form the tridimensional pyramid. The geometry of CuN3N*NCl chromophore is distorted square-pyramid. The superoxide-dismutase mimetic activity of the compound is measured and compared with those of the SOD enzyme, the …

research product

Spectroscopic, Magnetic, and Electrochemical Studies of a Dimeric N-Substituted-Sulfanilamide Copper(II) Complex. X-ray and Molecular Structure of the Cu(2)(sulfathiazolato)(4) Complex.

A copper(II) complex of formula Cu(2)(stz)(4) (stz(-) = sulfathiazolato) has been synthesized and characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic system, space group P2(1)cn with a = 10.595(7) Å, b = 14.274(3) Å, c = 29.65(1) Å, and Z = 4. The structure consists of dinuclear copper(II) units which contain four sulfathiazolato ligands bridging the metal ions through a nonlinear NCN group. The copper atoms are four-coordinated, the chromophore being CuN(4). The Cu.Cu bond distance is 2.671(2) Å. Magnetic susceptibility data in the temperature range 7-300 K show the occurrence of intramolecular antiferromagnetic coupling with 2J = -61.5 cm(-1). …

research product

Superoxide dismutase activity of ternary copper complexes of sulfathiazole and imidazole derivatives. Synthesis and properties of [CuL2(R-Him)2] [HL=4-amino-N-(thiazol-2-yl)benzenesulfonamide, R-Him=4-methylimidazole, 4,4-dimethylimidazoline or 1,2-dimethylimidazole]. Crystal structure of [CuL2(4,4-dimethylimidazoline)2]

Abstract New ternary copper(II) complexes of sulfathiazole (4-amino-N-(thiazol-2-yl)benzenesulfonamide)(HL) and methyl imidazole derivatives have been synthesised and characterised. The crystal structure of the complex [CuL2(4,4-dmHim)2] (1) [4,4-dmHim=4,4-dimethylimidazoline] has been determined. The copper centre has a quasi regular square planar environment with Cu-nitrogen bond lengths ranging from 1.952 to 2.010 A. From the spectroscopic properties of the complexes [CuL2(1,2-dmHim)2] (2) [1,2-dmHim=1,2-dimethylimidazole] and [CuL2(4-mHim)2] (3) [4-mHim=4-methylimidazole] a distorted tetragonal octahedral geometry is deduced. The compounds showed SOD mimetic activity in fact, a low conc…

research product

Metal complexes of sulfanilamide derivatives. Crystal structure of [Zn(sulfathiazole)2]·H2O

Abstract The crystal structure of the Zn(sulfathiazole) 2 ·H 2 O complex is reported. The complex crystallizes in the monoclinic space group C 2/ c . The cell dimensions are a = 9.098(3) A, b = 17.871(5) A, c = 14.61(1) A, β = 99.44(6)°, V = 2343(2) A 3 , Z = 4, and D x = 1.68 g/cm 3 . The final conventional R-factor = 0.027 for 2669 “observed” reflections and 191 variables. The Zn ion is surrounded in a regular tetrahedral arrangement by two N amino and two N thiazole atoms pertaining to four sulfathiazole (Hstz) ligands. Each stz anion, acting as a bidentate ligand, chelates to two Zn ions as a bridge through the N thiazole and the N amino atoms. The IR, 13 C NMR in solid state, 1 H NMR, …

research product